The invention relates to an audio system for a personal computer.
A recent trend in personal computing has been toward the multimedia computer, which provides high quality audio as well as video output. Such systems have typically included a pair of add-on speakers which are placed near the monitor and plugged into a sound board in the computer. In some cases, a microphone is also placed near the monitor to provide an input to the sound board. However, in such systems, the mobility of the speakers and the microphone relative to one another tends to frustrate attempts at echo cancellation, resulting in undesirable feedback.
As noted, upgrading an existing computing system to multimedia functionality typically requires a pair of add-on speakers and a plug-in sound board. However, use of add-on speakers consumes valuable desktop space and requires separate re-orientation of the monitor and speakers as the user changes position. Typically, over-the-counter multimedia computer systems have speakers that are built into the computer housing or built into the monitor or, in systems such as those currently marketed by IBM, built into the pedestal of the monitor. However, the audio components of these over-the-counter systems are not readily upgraded or replaced without replacing expensive associated equipment, such as a monitor.
In one aspect of the invention, an audio circuit for a multimedia computer is provided that comprises two speakers and a microphone. A driver is provided for driving the two speakers. A controller is connected to the driver for causing only one of the speakers to be driven while the computer is operating in a mode in which feedback through the microphone would otherwise occur.
In another aspect of the invention, an audio module for a computer monitor is provided which comprises a housing containing two speakers and a microphone which are mounted in fixed positions in the housing. The housing also contains circuitry having ports for receiving audio signals for the speakers and for delivering audio signals from the microphone.
In yet another aspect of the invention, a multimedia computer system is provided which includes a monitor and an audio module which is affixed to the monitor. The audio module contains a first speaker, a second speaker, and a microphone mounted in the audio module in a fixed relationship. The computer also contains a sound board comprising a means for driving both the first speaker and the second speaker when the system is in a speaker mode and for driving only one of the speakers when the system is in a speaker phone mode. The computer further comprises a means for applying a signal generated by the microphone to the sound board.
The invention also relates to a method of controlling an audio circuit of a multimedia computer which contains a first speaker, a second speaker, and a microphone. The method includes the step of controlling an audio circuit by supplying drive signals to both the first speaker and the second speaker when the audio circuit is in. a speaker mode. The method also includes the step of driving only one of the the speakers and receiving signals from the microphone when the audio circuit is in a speaker phone mode.